c＃-在字典中的列表内的对象中查找元素值

Question

I'm currently in needs of creating a Dictionary like that :

public Dictionary<MyFirstObject, List<MySecondObject>> _reference { get; set; }

These 2 objects store datas which need to be match during the process. This is why I used a Dictionary. The Objects looks like that :

public class MyFirstObject
{
    public string _element1 ;
    public MyThirdObject _element2;

    public MyFirstObject(string element1, MyThirdObject element2)
    {
        _element1 = element1;
        _element2 = element2;
    }
}
public class MySecondObject
{
    public string _element3;
    public string _element4;
    public string _element5;

    public MySecondObject(string element3, string element4, string element5)
    {
        _element3 = element3;
        _element4 = element4;
        _element5 = element5;
    }
}

---

Than I would like to get the " MyFirstObject " which contain some data inside, for example I succeed to find the " _element1 " and I got the related " MyFirstObject " of this request :

MyFirstObject mfo = _reference.FirstOrDefault(z => z.Key._element1 == "mySearch").Key

This code works ! I think that I could easily find the _element2 without problem. Now, I would like to do the same thing with the " Dictionary.Value " and find, for example, the " _element3 ".

I tried this code :

MyFirstObject mfo = _reference.FirstOrDefault(x => x.Value.FirstOrDefault(z => z._element3 == "mySearch")).Key;

I used the " .Key " at the end because I would like to get the relative " MyFirstObject " of this request. But this request doesn't work.

Can you help me to success this request please ?

Thanks

EDIT : the error message is : " Cannot implicitly convert type 'MySecondObject' to 'bool' "

Answer 1

var result = _reference.FirstOrDefault(x => 
                      x.Value.Any(z => z._element3 == "mySearch"));
if (result.Key != null)
    MyFirstObject mfo = result.Key;